other querymodes : Identifierquery Coordinatequery Criteriaquery Referencequery Basicquery Scriptsubmission TAP Outputoptions Help

2011ApJ...739L..30L - Astrophys. J., 739, L30 (2011/September-3)

A molecular EINSTEIN ring toward the z = 3.93 submillimeter galaxy MM18423+5938.

LESTRADE J.-F., CARILLI C.L., THANJAVUR K., KNEIB J.-P., RIECHERS D.A., BERTOLDI F., WALTER F. and OMONT A.

Abstract (from CDS):

We present high-resolution imaging of the low-order (J = 1 and 2) CO line emission from the z = 3.93 submillimeter galaxy (SMG) MM18423+5938 using the Expanded Very Large Array, and optical and near-IR imaging using the Canada-France-Hawaii Telescope. This SMG with a spectroscopic redshift was thought to be gravitationally lensed given its enormous apparent brightness. We find that the CO emission is consistent with a complete Einstein ring with a major axis diameter of ∼1".4, indicative of lensing. We have also identified the lensing galaxy as a very red elliptical coincident with the geometric center of the ring and estimated its photometric redshift z ∼ 1.1. A first estimate of the lens magnification factor is m ∼ 12. The luminosity L'_CO(1 - 0)_ of the CO(1-0) emission is 2.71±0.38x1011 m–1 K km/s pc2, and, adopting the commonly used conversion factor for ultraluminous infrared galaxies (ULIRGs), the molecular gas mass is M(H2) = 2.2x1011 m–1 M, comparable to unlensed SMGs if corrected by m ∼ 12. Our revised estimate of the far-IR luminosity of MM18423+5938 is 2x1013 m –1 < LFIR< 3x1014 m–1 L, comparable to that of ULIRGs. Further observations are required to quantify the star formation rate in MM18423+5938 and to constrain the mass model of the lens in more detail.

Journal keyword(s): galaxies: evolution - galaxies: high-redshift - galaxies: ISM - galaxies: starburst - gravitational lensing: strong - submillimeter: galaxies

Nomenclature: Text, Table 2: [LCT2011] JHHMMSS.ss+DDMMSS.s N=2.